The California Geologic Survey has published a new map of landslide susceptibility for the entire state of California. It addresses only deep-seated landslides, not shallow slides such as debris flows. The criteria used for developing the map included slope angle, geology, rock shear strength and history of landslides in a given area. You can download the map for free from the California Geologic Survey.
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Three Gorges landslide threat forces villagers to flee
Nearly 100 villagers living upstream from the Three Gorges dam have been forced to leave their homes under threat of a landslide, which officials fear was disturbed during the filling of the dam’s reservoir last year, Xinhua News Agency reported last week. Read on for more info. (Photo by enkai)
New Study Shows Odds High for Big California Quakes
Released: 4/14/2008 12:02:15 PM
California has more than a 99% chance of having a magnitude 6.7 or larger earthquake within the next 30 years, according scientists using a new model to determine the probability of big quakes.
The likelihood of a major quake of magnitude 7.5 or greater in the next 30 years is 46%-and such a quake is most likely to occur in the southern half of the state.
[Editor] At Left: Figure 1. The colors on this California map represent the UCERF probabilities of having a nearby earthquake rupture (within 3 or 4 miles) of magnitude 6.7 or larger in the next 30 years. As shown in the table, the chance of having such an event somewhere in California exceeds 99%. The 30-year probability of an even more powerful quake of magnitude 7.5 or larger is about 46%. [/Editor]
Allegations: Oregon Not Forthcoming With Landslide Hazard Information
Folks in Oregon are angry about a recent landslide and debris flow that closed Highway 30 and destroyed property in the town of Woodson. (Here is a powerpoint presentation by Bill Burns of the Oregon Department of Geology and Mineral Industries showing how the event happened). Some rather stinging allegations are being made that politicians withdrew a landslide hazard map from general use in 2002 for political reasons. That map or another one had characterized the area effected by the December 2007 debris flow as a "very high" or "extreme" risk of landslides. A very interesting article.